JPH0668010U - Fiber focusing device - Google Patents

Abstract

(57) [Summary] [Object] To provide a multi-port fiber coupler manufacturing apparatus which does not use a glass capillary. A first block member provided with a semicircular groove portion whose diameter continuously changes from a large diameter to a small diameter in a circumferential direction on a side surface of a cylinder, and a second block member having the same shape as these Using a clamp formed by arranging the block member so that the groove portions are in contact with each other with the same diameter, a plurality of fibers are sandwiched in this groove portion, and the contact portion on the cylindrical side surface of the block member is moved to contact the contact portion. The fiber diameter is pressed by changing the groove diameter.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an apparatus for concentrating a large number of fiber bundles, such as an apparatus for manufacturing a multiport fiber coupler which is a basic component of an optical communication system.

[0002]

[Prior art]

 A multi-port fiber coupler has an optical coupling part that is formed by heating and fusing multiple optical fibers, and is used to branch or couple lines between optical transmission lines in optical communication systems. It is a basic part used. Regarding the multi-port fiber coupler, there is a report of ELECTRONICS LETTERS 25TH APRIL1991 VOL.27 NO.9. In this document, for example, in the case of a 1x19 fiber coupler, one fiber is bundled in a circle with one fiber in the center, six fibers in the outer circumference, and twelve fibers in the outer circumference. The ones with are listed.

[0003]

[Problems to be solved by the device]

 However, in the case where the glass capillaries are attached and the fibers are adhered to each other as described above, there are the following problems.

First, since the inner diameter of the glass capillaries is small and is almost the same as the diameter when the fibers are bundled, it is very difficult to pass as many as 19 fibers therein, and a special device is required. And

Further, in an actual fiber, a fiber protective coating is applied to the outside of a glass portion including a core and a clad. As an example of the dimensions of such a coated fiber, the diameter of the central glass portion is 125 μm, whereas the diameter of the coated fiber is 250 μm. Therefore, when manufacturing a fiber coupler with an actual coated fiber, if the coated fiber (250 μm) is simply passed through the capillary, the glass part cannot be adhered due to the thickness of the coating, and the inside of the glass capillary is eventually closed. It was not possible to make a fiber coupler unless all the fiber coatings were stripped off before passing through, then bare fibers were bundled and passed through a glass capillary.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a device for bundling fiber bundles with a simple configuration.

[0007]

[Means for Solving the Problems]

 The fiber concentrating device of the present invention made to solve the above problems has two blocks, at least one of which rotates while contacting the surfaces thereof, and a contact surface of each block along the contact rotation direction. A groove having a substantially semicircular cross section, which is provided so as to face each other and whose contact rotation is gradually reduced from the start point to the end point, has a semi-circular groove. It is characterized in that the diameter of the circular hole formed at the contact point is gradually reduced, and the fiber bundle sandwiched in the circular hole is clamped and bundled. Hereinafter, the operation of the device for manufacturing a fiber concentrator of the present invention, for example, a multiport fiber coupler will be described.

[0008]

[Action]

 According to the present invention, first, the block member is placed in a state in which the groove portions having the largest groove diameter are in contact with each other, and a plurality of fibers are provided in the groove having the largest diameter (a circular hole is formed by two grooves). Passed through. This fiber is provided with a portion where the glass is exposed by removing a part of the coating of the fiber in advance (hereinafter referred to as a bare fiber portion). Then, the groove with the largest diameter is positioned so that the portion near the coated end of the coated fiber, which is the boundary with the bare fiber portion, contacts the groove. From this state, the diameter of the circular hole formed at the contact point is continuously reduced by moving the contact portion while contacting the two block members. As the diameter of the circular hole becomes smaller, the fiber inserted in the circular hole is pressed and brought into close contact. Then, the diameter of the circular hole becomes smaller, and the bare fibers are brought into close contact with each other. Then, the bare fiber portion is melt-drawn and the fiber coupler is formed.

[0009]

【Example】

 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view of an embodiment of a clamp in a fiber focusing device according to the present invention, and FIGS. 2 and 3 show two states of the clamp. Of these, FIG. 2 illustrates a state (state A) when the fiber coating portions are first bundled and fixed. (A) is a left side view, (b) is a front view, and (c) is a right side view. is there. 3A and 3B are diagrams for explaining the state (state B) when the bare fiber portion is being pressed. (A) is a left side view, (b) is a front view, and (c) is a right side view.

In the figure, 1 is a first block member, 2 is a second block member, 1A and 2A are cylindrical axes, 3 and 4 are groove portions, 3A and 4A are maximum grooves, 3B and 4B are minimum grooves, and 5 and 6 are shown. Is the maximum groove side end face, and 7 and 8 are the minimum groove side end faces. The clamp 10 is formed by these first and second block members.

In the present embodiment, the block members 1 and 2 in the shape of a cylinder are used in which the angles formed by the end faces 5 and 6 on the maximum groove side and the end faces 7 and 8 on the minimum groove side are right angles, but this angle is the fiber coating portion. An appropriate angle may be set according to the length from to the melt-stretched portion of the bare fiber portion. The groove portions 3 and 4 are semicircular grooves, and the diameter thereof continuously changes from the large diameter to the small diameter in the circumferential direction of the block members 1 and 2. That is, the maximum groove-side end surfaces 5 and 6 having the largest groove diameter are continuously changed to the minimum groove-side end surfaces 7 and 8 having the smallest groove diameter. The block members 1 and 2 are arranged so as to contact each other at one point on the circumferential surface in the front view (point contact in the front view, but line contact in the side view). When the contact portion is viewed from a side view, the groove portion 3 and the groove portion 4 are opposed to each other so that they are always in contact with each other with the same diameter. Therefore, since the semi-circular grooves having the same diameter of the groove portions 3 and 4 face each other, a circular hole is formed. The groove diameters of the maximum grooves 3A and 4A are set so that the circular holes formed by them can pass through the fiber coating portion in a circular bundle, and the groove diameters of the minimum grooves 3B and 4B are set by these. The circular hole to be formed is set to a size that allows the bare fiber portion to be in close contact with the circular shape.

Next, the operation and operation of this embodiment will be described. FIG. 4 is a diagram for explaining the movement when the fibers are in close contact with each other, and FIG. 4A illustrates an initial state (hereinafter referred to as state A) when the fiber coating portions are bundled and fixed, and FIG. Describes a final state (hereinafter referred to as state B) in which the bare fiber portion is pressed. In this example, seven fibers are closely attached.

As shown in FIG. 4A, a coated fiber having a bare fiber portion provided in advance is prepared and sandwiched in the circular hole of the clamp 10 in the state A. The circular hole in the state A is a size that allows the fiber coating portions to be bundled and passed through as described above. Then, the coated end of the fiber coating portion is positioned so that it is just positioned in the circular hole of the clamp 10. In the bare fiber portion in this state, there is a gap between the fiber lines (a gap of 125 μm when the bare fiber diameter is 125 μm and the coated fiber diameter is 250 μm).

Next, from this state, the contact portions of the two block members 1 and 2 are moved while contacting their cylindrical side surfaces. That is, the contact portion on the side surface of the cylinder is continuously moved by sliding the cylinder axis 1A, 2A in the lateral direction without changing the distance between the cylinder axes 1A, 2A of each block member. When the contact portion on the side surface of the cylinder moves, the circular hole becomes smaller accordingly, and eventually the state B shown in (b) is reached. Here, the circular hole is minimized and the bare fiber part comes into close contact with the circular shape. In this state, since the respective fiber wires of the bare fiber portion are in close contact with each other without any gap, they can be partially heat-sealed and stretched to manufacture the target fiber coupler.

In this embodiment, the case of manufacturing seven fiber couplers has been described. However, if the groove diameter is designed according to the number of fibers, the present invention can be implemented regardless of the number.

Further, although the groove portion is provided on the side surface of the cylinder in this embodiment, only the groove portion and the vicinity thereof may have the cylindrical surface.

Further, as a modified embodiment of the present invention, it is possible to form the clamp by two block members having different contact surface curvatures, or one or both of them may be an elliptic block member. When the curvatures of the two block members are changed, the block member having the larger curvature may be rotated without moving the one having the smaller curvature.

[0018]

[Effect of device]

 As described above in detail, according to the present invention, two circular block members each having a groove whose diameter is continuously reduced are brought into contact with each other so that the circular hole formed at the contact point becomes gradually smaller. By moving the contacts, the fiber bundle inserted into the circular hole can be sandwiched by gently bundling it without making the fiber bundles stick to each other during the initial insertion. Since the fibers are tightly bundled, a dense fiber bundle can be formed with a device having a very simple structure and a simple operation.

Further, according to the present invention, it is possible to manufacture a multi-port fiber coupler without using a glass capillary when forming the multi-port fiber coupler. Therefore, the number of parts is reduced, the manufacturing process can be simplified, and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of a clamp in a fiber coupler manufacturing apparatus of the present invention.

2A and 2B are views for explaining a clamped state when the fiber coating portions are first bundled and fixed, FIG. 2A is a left side view, and FIG.
Is a front view, (c) is a right side view

3A and 3B are diagrams illustrating a clamped state when a bare fiber portion is pressed, FIG. 3A is a left side view, and FIG. 3B is a front view.
(C) Right side view

FIG. 4 is a diagram for explaining the movement when the fibers are closely attached, (a) is an initial state when the fiber coating portions are bundled and fixed, and (b) is a final state when the bare fiber portion is pressed.

[Explanation of symbols]

 1: 1st block member 2: 2nd block member 1A, 2A: cylindrical axis 3, 4: groove part 5, 6: maximum groove side end surface 7, 8: minimum groove side end surface 10: clamp

Claims (1)

[Scope of utility model registration request] 1. Two blocks, at least one of which rotates while their surfaces are in contact with each other, and a contact surface of each block which faces each other along the contact rotation direction, and which extends from a contact rotation start point to an end point. Has a groove having a substantially semicircular cross section, the width of which is gradually reduced toward the bottom, and the diameter of the circular hole formed at the contact point is gradually reduced with the rotation of at least one of the blocks. A fiber concentrating device that moves and clamps and bundles the fiber bundle sandwiched in the circular hole.